Traditionally, slot machines include a number of rotating reels each having an outer circumferential reel strip printed with a number of play symbols usually consisting of items such as pictures of fruit, playing cards or other symbols. The reels are located in a side by side relationship for independent movement about a common axis. In the more modern machines each of the reels are driven individually by a stepper motor that serves to rotate the reels about the common axis.
Slot machine play is initiated when a player either pulls a handle or pushes a button on the slot machine. Such player action, in turn, triggers the start of the reel motors which rotate the reels. The reels are then stopped at random positions usually under control of a microprocessor. Upon completion of the rotation of all of the reels, the machine determines if the player has won a payout according to the given combinations of the play symbols displayed along a pay line.
In order to house the reels, conventional slot machines require a housing having a depth sufficient to accommodate the reels. These reels can be mounted on modules or reel mounting mechanisms which can each be separately inserted into the housing. Upon insertion, it has been conventional to secure the module to the housing by bolting the module to an internal structure in the housing and then to cable or provide electrical connections to a reel motor and other electronic components. In addition to being relatively expensive to manufacture, it is usually a very cumbersome procedure to remove these modules from the housing for maintenance or modifications of the machines.
Moreover, the reels mounted on the modules should have precise alignment with the pay line located on a reel display window. The modules, are secured next to each other, as noted above, in a side by side relationship for independent reel movement about a common axis. This has created certain difficulties during the manufacture and maintenance of slot machines utilizing such modules. For example, one of the major problems is to accurately align the centers of the play symbols with the pay line. In most slot machines this requires a time consuming and tedious adjustment of a number of inaccessible elements within the machine housing. As a result, adjusting the alignment of the reels during the manufacture of slot machines as well as the maintenance of slot machines presents significant problems to the industry.